Suppose a chromium atom in the oxidation state formed a complex with one chloride anion and five water molecules. Write the chemical formula of this complex.

[CrCl(H₂O)₅]²⁺

Explanation:

Oxidation Number of Chromium = +3

Oxidation Number of Chloride = -1

Oxidation Number of Water molecules = 0

Since the complex contains one chloride atom (Cl), 5 water molecules (H₂O) and one chromium atom (Cr). We have;

CrCl(H₂O)₅

The oxidation number of the mixture is given as;

+3   + (-1)  + 5(0) = x

x = + 3 - 1 + 0

x = +2

The chemical formular of the complex is;

[CrCl(H₂O)₅]²⁺

c (diamond),

sio2 (quartz)